Hey guys, I need some help. This is probably either something real easy or something incredibly confusing.

Anyways, i took my car for a smog yesterday. The only problem they said i had was with my ignition timing. The quote they repeated was "out of tolerance". More specifically, this problem seems to be when my car is on idle. Now he is where im really unclear. I think i need to lower my bTDC to 10* degrees and 750rpm. that or thats where it is now, need to raise it.

i do not know car lingo. My car is a 1993 toyota paseo, so it is 4 clylander. I'm gonna be one for another couple hours until im out of class, and then i should call someone on this. Until then, u guys are all i got. Thanks!

Mr. Crackerz wrote:Hey guys, I need some help. This is probably either something real easy or something incredibly confusing.

Anyways, i took my car for a smog yesterday. The only problem they said i had was with my ignition timing. The quote they repeated was "out of tolerance". More specifically, this problem seems to be when my car is on idle. Now he is where im really unclear. I think i need to lower my bTDC to 10* degrees and 750rpm. that or thats where it is now, need to raise it.

i do not know car lingo. My car is a 1993 toyota paseo, so it is 4 clylander. I'm gonna be one for another couple hours until im out of class, and then i should call someone on this. Until then, u guys are all i got. Thanks!

This is easy because you have no choice. You can't fix it yourself, clearly, so go find an independent shop that specializes in Toyotas, or the dealer. Either will probably have dealt with the problem before and not have to spend too much time figuring it out.

Usually the problem is in the oxygen sensor or the mass air flow meter. You haven't messed with bogus "performance" add-ons, have you? Or let guys that "know all about cars" mess with yours?

Mr. Crackerz wrote:Hey guys, I need some help. This is probably either something real easy or something incredibly confusing.

Anyways, i took my car for a smog yesterday. The only problem they said i had was with my ignition timing. The quote they repeated was "out of tolerance". More specifically, this problem seems to be when my car is on idle. Now he is where im really unclear. I think i need to lower my bTDC to 10* degrees and 750rpm. that or thats where it is now, need to raise it.

i do not know car lingo. My car is a 1993 toyota paseo, so it is 4 clylander. I'm gonna be one for another couple hours until im out of class, and then i should call someone on this. Until then, u guys are all i got. Thanks!

This is easy because you have no choice. You can't fix it yourself, clearly, so go find an independent shop that specializes in Toyotas, or the dealer. Either will probably have dealt with the problem before and not have to spend too much time figuring it out.

Usually the problem is in the oxygen sensor or the mass air flow meter. You haven't messed with bogus "performance" add-ons, have you? Or let guys that "know all about cars" mess with yours?

haha thanks carlgo, i forgot about this, i did fix it, it needed some adjustment with a timing light gun, and yeah, all good after that

Crakerz wrote:Hey guys, I need some help. This is probably either something real easy or something incredibly confusing.

Anyways, i took my car for a smog yesterday. The only problem they said i had was with my ignition timing. The quote they repeated was "out of tolerance". More specifically, this problem seems to be when my car is on idle. Now he is where im really unclear. I think i need to lower my bTDC to 10* degrees and 750rpm. that or thats where it is now, need to raise it.

i do not know car lingo. My car is a 1993 toyota paseo, so it is 4 clylander. I'm gonna be one for another couple hours until im out of class, and then i should call someone on this. Until then, u guys are all i got. Thanks!

sorry to here your car's not feeling well.

and don't worry, you're not dumb, it's incredibly confusing.

I'm no mechanic but I do know a little about cars.

If you were close to passing last time, and you can't fork out the $$$ to have it fixed right now, do this (actually I'd do this even if you just had it fixed. none of these procedures will hurt your car):

GENERAL TIPS TO PASSING SMOG CHECKS:
1) VERY IMPORTANT Drive your car up and down the Highway for maybe 20 or 30 minutes right before your Smog Check. The point is you want to get your catalytic converter really really really hot. the Platinum in it (which cleans your exhaust) actually works better the hotter it is
2) Fill up with high price gas and even add one of those valve/engine/fuel cleaners additives to your tank. I've heard both of these don't do much but neither will hurt, and it will help your car burn cleaner. If you don't know what I'm talking about when I say fuel additive, buy one of these at your local gas station:
3) I think half-full tank of gas is good... Definitely do NOT get a smog check on empty - all the crud at the bottom of you tank gets thrown in with the mix and that will fuc up your emissions

-beyond those 3 things you can't do much to your car without the help of a professional

now onto explaining what's wrong with your car.
keep in mind, I have no idea how much of this you know, so I will try to explain everything. gimme a break

If you don't know internal combustion engines compresses oxygen and fuel into a chamber (cylinders), then basically "light a match" from ignition/spark-plug. the explosion causes the gas mixture to expand and uses that explosion to drive your car forward.

you have 2 valves on the top of each chamber. one to let in oxygen/fuel and one let out the post explosion waste. if you can't picture what I'm talking about, check this:

the thing is your valves and pistons wear down over time and get slower. your ignition, which is almost completely separate, stays the same unless you adjust it (because it's powered by a small computer inside your car). the ignition is almost built too well so it doesn't wear down with the rest of the engine. valves and ignition need to be in sync for your car to get work properly.

if they're out of sync:

I) you'll get less power
II) you'll waste more gas
III) you won't pass a smog check

Rather than adjusting all the complex valves, gears, cams, pistons, etc. to get back up to speed with your ignition, it's easier to just retard the ignition a little.

delaying aka retarding or "lowering" will stall the ignition a few millisecs allowing a little more compression before the explosion. higher compression will heat up the reactants more, which will help cause more reactions with the gas and oxygen and will thus be more efficient (causing the opposite of I, II, III above)

strangely, at low RPM's like when you idle, the oxygen does not flow into the chamber as fast as when it does when you're driving it full throttle down the highway. therefore you tend to have a gas heavy engine at low speed and an oxygen heavy engine at high speed. there is an O2 sensor that measures the the oxygen coming into the chamber, calculates how much Gas is needed and then throws in the correct amount. a lot of times a new O2 sensor is what's need. However in your case, the sensor is fine (i guess according to your mechanic) and you just need the timing of your 'plugs adjusted (or you need new plugs). the combo of low oxygen and low gas and a bad sparkplug timing fvcks with emissions I guess.

to combat that problem
you either need
a) a new O2 sensor
b) an adjustment of the timing belts, or cams, or ignition, etc.
c) a new Cat Converter (which "cleans" the exhaust)
d) new sparkplugs - usually not a smog check issue, you would notice misfires and your engine would have "mini-stalls" and would be more of a performance problem rather than emission prob.
e) all of the above

I've already had A, C, and D done to my car in the 5 years I've owned it, so don't feel bad.

like I said the adjustment of ignition timing requires $$$ complex instruments which common people have no reason to own. pick a mechanic you trust and relax, there's nothing you can do to help the situation

Last edited by first off on Thu Sep 25, 2008 5:47 pm, edited 2 times in total.